Position Indicator

The present disclosure relates to a position indicator (stylus) for use with a position detection system.

As a position inputting apparatus configured from a position detection system and a position indicator called electronic pen is configured in various types such as, for example, an electromagnetic coupling type and a capacitive coupling type depending upon the difference in the coupling method between a sensor of the position detection system and the electronic pen.

Even if position inputting apparatus are of the same type, various configuration types are available depending upon the difference between the exchange method of a stylus position signal between the sensor of the position detection system and the position indicator and the method for exchange of, between the position detection system and the position indicator, additional information such as operation information of a switch provided on the position indicator, pen pressure information, identification information of the position indicator and internal storage data or for exchange of instruction information for changing the action of the position indicator. Conventionally, a position indicator compatible with a position detection system is provided to a user while a method for a stylus position signal and a method for exchange of additional information are restricted to particular methods. Therefore, since it is necessary for a utilizer to have a position indicator for exclusive use for a position inputting apparatus which includes a position detection system having a similar position detection sensor, it is necessary for the utilizer to carry a plurality of position indicators and select a suitable position indicator for every position inputting apparatus.

For example, for a position indicator of the capacitive coupling type, a plurality of configuration types as described below is available. In particular, the position indicator of the first configuration type is a position indicator of a type (passive type) wherein a stylus position signal is not sent from the position indicator but a change of energy (or a voltage) induced in a conductor of a sensor of a position detection system at a position at which the position indicator is disposed when alternating electric field energy sent from the sensor of the position detection system is supplied to the earth (ground) via the position indicator and the human body is detected to perform position detection (refer to, for example, Patent Document 1 (Japanese Patent Laid-Open No. 2011-3035) and so forth).

Meanwhile, the position indicator of the second configuration type of the capacitive coupling type is an improvement of the first configuration type described above in regard to its low sensitivity in position detection and is a position indicator of the type wherein a signal is received from a sensor of a position detection system and is then fed back to the sensor after signal processing such as signal enhancement is performed for the received signal (improved type of the passive type) (refer to, for example, Patent Document 2 (Japanese Patent No. 4683505) and so forth). In the case of the position indicators of the first and second configuration types, additional information is transmitted or exchanged to the position detection sensor using, for example, a wireless communication circuit.

The position indicator of the third configuration type of the capacitive coupling type is, different from those of the first and second configuration types described above, a position indicator of the so-called active type wherein the position indicator includes an origination circuit and an origination signal from the origination circuit is supplied as a stylus position signal to the position detection sensor (refer to, for example, Patent Document 3 (Japanese Patent Laid-Open No. Hei 07-295722) and so forth). Although a sensor panel of a position detection circuit is used as the position detection system, position detection of a position indicated by the position indicator is performed from signal intensities of individual conductors which receive the origination signal from the position indicator of the active type.

In the case of such position indicators of the third configuration type, the position indicators are further classified into a plurality of types including a configuration type wherein all of additional information is sent to and received from the position detection system together with a stylus position signal and another configuration type wherein part of additional information is sent and received together with a stylus position signal while the other additional information is transmitted separately to a wireless communication circuit provided in the position detection system via a wireless communication circuit.

It is to be noted that, although detailed description is omitted, it is similar to the capacitive coupling type described above that, also in the electromagnetic coupling type, there exist a plurality of configuration types including a configuration type wherein the position indicator receives a signal from a sensor of the position detection system by a resonance circuit and the received signal is fed back to the sensor of the position detection system and another configuration type wherein an origination circuit is provided and an origination signal from the origination circuit is transmitted to a sensor of the position detection system via the resonance circuit as well as a configuration type wherein additional information is transmitted to a wireless communication circuit which transmits the additional information to a wireless communication circuit provided in the position detection system.

Incidentally, in the past, even with position inputting apparatus of the same capacitive coupling type or electromagnetic coupling type, a position indicator compatible with a configuration type must be prepared for each of a plurality of different configuration types as described above. However, that a position indicator must be prepared for each of different configuration types in this manner imposes a burden in terms of the cost on its user and the user must manage the position indicators of the plurality of configuration types for compatibility with the position detection system, which is cumbersome.

It is an object of the present disclosure to solve the problems described above and provide a position indicator with which a plurality of configuration types can be utilized singly.

In order to solve the problems described above, the present disclosure provides a position indicator, including: a communication circuit which, in operation, communicates with an outer device; a configuration circuit which, in operation, performs an initial setting process based on a signal from the outer device, an initial setting of at least one switch circuit being set by the initial setting process; a signal generation circuit which, in operation, generates a stylus position signal; and a control circuit which, in operation, controls transmission of the stylus position signal based on the initial setting set by the initial setting process performed by the configuration circuit, and controls reception of a signal received from the outer device.

In the position indicator according to the present disclosure having the configuration described above, the configuration circuit performs the initial setting for the position indicator based on the signal from the outer device received by the communication circuit. This initial setting can include switching setting of a plurality of configuration types. Further, the control circuit controls transmission of the stylus position signal on the basis of the initial setting process performed by the configuration circuit and the signal from the outer device.

Consequently, the position indicator according to the present disclosure can be configured to be compatible with various types of position detection systems.

Since the position indicator according to the present disclosure can adopt, in response to a configuration type of a position detection system, a configuration (mode) compatible with the configuration type, there is no necessity to prepare a position indicator for each of a plurality of position detection systems of different configuration types. Therefore, the burden on a user in terms of cost can be reduced. Further, since only it is necessary for the user to prepare a single position indicator common to position detection systems of a plurality of configuration types, an effect is achieved that the necessity for cumbersome management for compatibility with a position detection system is eliminated.

In the following, embodiments of a position indicator according to the present disclosure are described with reference to the drawings.is a view generally depicting a conceptual configuration and a processing action of a position indicatorof according to one or more embodiments of the present disclosure and is a view illustrating a state in which the position indicatoris positioned on a sensor inputting faceof a position detection systemof the capacitive type. Meanwhile,are views illustrating an example of a mechanical configuration of the position indicator, whereinis a partial vertical sectional view andis a view depicting part of an appearance of the position indicator. In the present embodiment, the position indicatoris formed such that an appearance thereof has a shape of a bar-like stylus.

The position indicatorof the present embodiment includes a bar-like housing. The housingis configured from an insulator portionof a hollow cylindrical shape made of an insulating material, for example, a synthetic resin as depicted in. In the present embodiment, an outer circumferential face of the insulator portionof the housingis covered, at least at a portion thereof at which an operator grasps the position indicator, with a conductor portionmade of, for example, a metal.

In the housing, a printed circuit board, a batteryand a pen pressure detection circuitare disposed as depicted in. The conductor portionwhich covers the outer circumferential face of the housingis, though not depicted, electrically connected to a grounding conductor of the printed circuit board.

On the printed circuit board, a signal transmission control circuit, a wireless communication circuit, a side switchconfigured from a pushbutton switch, an identification (ID) memoryfor storing ID information of the position indicator, oscillatorsandwhich output oscillation signals of frequencies fand fdifferent from each other, and wiring patterns such as conductive patternstoare disposed as depicted inand. Further, in the present example, a power supply switch, an LED (Light Emitting Diode)and so forth are disposed as depicted in. It is to be noted that, while, in, the conductive patternstoare schematically depicted as a single conductive pattern for the simplification of the illustration, naturally there also is a case in which the conductive patternstoare configured from a plurality of conductive patterns as occasion demands.

The batteryis a supply source of power to electronic circuits and electronic parts configured on the printed circuit board. The pen pressure detection circuitis configured as a variable capacitor which demonstrates a capacitance corresponding to a pen pressure applied to a center electrodewhich configures a core member.

The wireless communication circuitconfigures an example of a communication circuit (first communication circuit) in the present disclosure and has a transmission circuit which is an example of a first transmission circuit and a reception circuit which is an example of a first reception circuit which receives a signal from the position detection system. In the present embodiment, the wireless communication circuitis configured as a wireless communication circuit which complies with the Bluetooth (registered trademark) standard of a short-range wireless communication standard. The wireless communication circuitis connected to the signal transmission control circuit. It is to be noted that the wireless communication circuitmay not comply with the Bluetooth but may be, for example, that by infrared communication, or a wireless communication circuit which complies with the Wi-Fi (registered trademark) standard may be used.

The side switch, ID memoryand pen pressure detection circuitindividually configure an additional information generation circuit. The side switchsupplies on or off information thereof as an example of additional information to the signal transmission control circuit. The ID memoryoutputs identification information (ID: Identification) of the position indicatorstored therein as an example of additional information to the signal transmission control circuitin response to a readout request from the signal transmission control circuit. The variable capacitor configured from the pen pressure detection circuitdemonstrates a capacitance variation in response to a value of a pen pressure applied to the center electrodewhich configures the core member, and the signal transmission control circuitgenerates pen pressure information as an example of additional information on the basis of the capacitance.

The oscillatorsandgenerate alternating signals for forming a stylus position signal to be sent from the position indicatorof the present embodiment and supply the generated alternating signals to the signal transmission control circuit. In the present embodiment, the oscillatorgenerates an alternating signal of the frequency fand the oscillatorgenerates an alternating signal of the frequency fdifferent from the frequency f. The signal transmission control circuitgenerates different stylus position signals on the basis of the oscillatorand the oscillator. In particular, the signal transmission control circuitcooperates with the oscillatorand the oscillatorto configure a circuit for generating a stylus position signal and configure two origination circuits. The signal transmission control circuituses one of the two generated stylus position signals as a stylus position signal to be sent from the position indicator. It is to be noted that, in place of the oscillatorsand, a plurality of origination circuits which generate and originate stylus position signals for a plurality of position indicators of different configuration types of the active type hereinafter described may be provided and are selectively controlled by the signal transmission control circuit.

Further, in the present embodiment, the batteryis configured such that it is accommodated in the housingin such a manner as depicted inand, and a power supply voltage for an electronic circuit such as the signal transmission control circuiton the printed circuit boardis generated by the battery. In, a terminalis a terminal electrically connected to the power supply circuit on the printed circuit board. A positive side electrodeof the batterycontacts with and is electrically connected to the terminal. Though not depicted, a negative side electrode of the batteryis connected directly to the grounding conductor of the printed circuit boardor is pressed against and contacted with a terminal which is connected to the grounding conductor of the printed circuit boardvia the conductor portionof the housingand is elastically displaced.

An operation elementof the power supply switchdisposed on the printed circuit boardis provided for operation from the outside through an opening provided in the housingas depicted in. If the user slidably moves the operation element, then the power supply switchcan be switched on or off. It is to be noted that, while also a power supply circuit for generating a power supply voltage from the voltage of the batterywhen the power supply switchis on is formed on the printed circuit board, it is omitted for simplified illustration in.

One end portion side in a direction of a center axis of the insulator portionof a hollow cylindrical shape configuring the housingis formed as a tapering portionwhich tapers gradually as depicted in. To an outer circumference side of the tapering portion, a peripheral electrodemade of, for example, an annular conductive metal is attached. The peripheral electrodeand the conductor portionon the outer circumferential surface of the housingare isolated from each other by the insulator portioninterposed therebetween.

As schematically depicted in, the peripheral electrodecapacitively couples with the position detection systemto configure, in the present embodiment, a reception circuit for a signal from the position detection system. The peripheral electrodeis electrically connected to the conductive patternof the printed circuit boardby a lead conductor memberextending through the insulator portion. The conductive patternis connected, in the present example, to an input terminal of the signal transmission control circuit.

Further, in the present embodiment, the center electrodeconfigured from a bar-like member having conductivity is disposed such that one end side thereof projects to the outside from the hollow portion of the tapering portionof the housing. This center electrodeserves as a core member configuring a pen tip of the position indicatorof a shape of a pen.

The center electrodeconfigures, in the present embodiment, an example of a second transmission circuit for transmitting a stylus position signal and is configured such that an end portion on the opposite side to the side on which it projects to the outside is electrically connected to the conductive patternformed on the printed circuit board. The conductive patternis connected to an output terminal of the signal transmission control circuit. It is to be noted that, in the present embodiment, the position indicatoracts as a position indicator of the passive type which does not transmit a stylus position signal, and in this case, the center electrodeplays a role for sucking up charge from a conductor of the position detection systemvia a capacitive coupling portion.

The peripheral electrodeis provided around the center electrode. The combination of the peripheral electrodeand the center electrodeis for a position indicator of the improved type of the passive type described hereinabove. In the present embodiment, a shield memberfor effectively preventing electric interference between the peripheral electrodeand the center electrodeis provided between the peripheral electrodeand the center electrode. The shield memberin the present embodiment is provided so as to surround the center electrode. Consequently, the shield memberis interposed between the peripheral electrodeand the center electrodeto minimize the coupling capacitance between the peripheral electrodeand the center electrode.

It is to be noted that also the center electrodeand the peripheral electrodeconfigure a communication circuit (second communication circuit), and although it is described in the foregoing description that the center electrodeconfigures a transmission circuit (second transmission circuit) and the peripheral electrodeconfigures a reception circuit (second reception circuit), the peripheral electrodeand the center electrodemay otherwise be configured such that the center electrodeconfigures a reception circuit (second reception circuit) and the peripheral electrodeconfigures a transmission circuit (second transmission circuit).

The center electrodeas a core member is fitted, at an end portion thereof on the opposite side to the side on which it projects to the outside, with the pen pressure detection circuitdisposed in the hollow portion of the housingsuch that it is locked in the hollow portion of the housingof the position indicator. It is to be noted that, as hereinafter described, the center electrodeis configured such that, if it is pulled out, then it is brought out of fitting with the pen pressure detection circuit. In other words, the center electrodeas a core member can be replaced from the position indicator.

The pen pressure detection circuitis configured, in the present example, as a variable capacitor which demonstrates a capacitance corresponding to a pressure (pen pressure) applied to the center electrodeas a core member (refer to, for example, Japanese Patent Laid-Open No. 2011-186803). The electrodes at the opposite ends of the variable capacitor configuring the pen pressure detection circuitare connected, in, to the signal transmission control circuitby the conductive pattern

The signal transmission control circuitperforms determination control in regard to which one of a plurality of configuration types (modes) is to be applied to the position indicatorof the present embodiment on the basis of information received from the outside via the wireless communication circuitor information received via the peripheral electrode. Further, the signal transmission control circuitperforms transmission control of a stylus position signal through the center electrodeon the basis of the determination control. Furthermore, the signal transmission control circuitperforms transmission control of additional information through the center electrodeor the wireless communication circuit.

[Initial Setting of Position Indicatorof Embodiment and Synchronization Based on Signal from Position Detection System]

In the present embodiment, as the position detection systemto be used with the position indicator, those of a plurality of configuration types such as the passive type, the improved type of the passive type and the active type are available as described hereinabove. In the present embodiment, where the position detection systemincludes a wireless communication circuit capable of communicating with the wireless communication circuitof the position indicator, pen type information indicative of a configuration type with which the position detection systemcan act is transmitted to the position indicatorby the wireless communication circuit. The position indicatorreceives the pen type information from the position detection system using the reception function of the wireless communication circuit(example of a reception function of the communication circuit), determines, on the basis of the received pen type information, to which one of the configuration types (modes) the position indicator is to be set, and initially sets so that the position indicatorhas a configuration of a position indicator of the determined configuration type.

In the case of a position indicator of the configuration type of the passive type or the improved type of the passive type in which a transmission signal from the position detection systemside is received, the position indicatordetermines to which one of the configuration types the position indicator is to be set by receiving a signal from the position detection system through the peripheral electrode(example of the reception function of the communication circuit), whereafter an initial setting is performed so that the position indicator has a configuration of the determined type.

In this case, the passive type and the improved type of the passive type have a difference in frequency of a signal from the position detection system and a difference in signal contents (difference in spread code, difference in modulation method and so forth). Therefore, the position indicatordecides the differences and determines which configuration type the position indicator is to have from a result of the decision. In this case, also when information indicating a configuration type cannot be acquired from the position detection system via the wireless communication circuit, it can be decided which configuration type (mode) the position indicator is to have.

The signal transmission control circuitof the position indicatorperforms an initial setting based on a determination process of the configuration type (mode) of the position indicatoron the basis of information received from the position detection systemvia the wireless communication circuitor a signal received via the peripheral electrodeas described hereinabove. The signal transmission control circuitperforms a process for controlling the position indicatorto perform, in the initially set configuration type (mode), transmission of a stylus position signal and additional information synchronized with a signal received from the position detection system via the wireless communication circuitor the peripheral electrode.

Now, a process for the initial setting and the synchronization described above in a case in which the position indicatorperforms an initial setting on the basis of information received from the position detection systemvia the wireless communication circuitand transmits a stylus position signal and additional information to the position detection systemby the synchronization based on a signal received from the position detection systemvia the wireless communication circuitis described with reference to a timing chart of.

In the present example, the position indicatortransmits a signal Sp for pairing with the position detection systemfor communication connection intermittently in a fixed period To to the position detection systemvia the wireless communication circuitas depicted in row A ofuntil after so-called pairing between the position indicatorand the position detection system, which is a state in which the position indicatoris connected for communication to the position detection systemvia the wireless communication circuit, is completed.

After the position detection systemconfirms reception of the signal Sp for pairing from the position indicator, it determines that pairing thereof with the position indicatoris possible and sends, in the present example, information indicating a configuration type of the position indicator which is to act together with the position detection system to the position indicator.

If the position indicatorconfirms reception of the information indicating a configuration type from the position detection system via the wireless communication circuit(refer to row A of), then it determines that pairing with the position detection systemis possible and performs an initial setting using the received information indicating the configuration type. In particular, in the present example, the information indicating a configuration type is an example of information for the initial setting in the position indicator.

This initial setting includes, for example, setting of a frequency of a signal to be sent from the position indicator, selection of a signal to be sent from the position indicator(selection of a stylus position signal and additional information), and a transmission timing of a signal to be sent from the position indicator(for example, in the case of transmission of one piece of data for each external synchronizing signal, in the case where no external synchronizing signal is available and transmission is repeated at designated intervals or in a like case).

In particular, the position indicator, on the basis of the information indicating a configuration type as an example of setting information from the position detection system, determines a frequency of a transmission signal to be transmitted from the pen tip, determines a period of a continuous signal to be transmitted from the pen tip, determines from which one of the pen tip and the wireless communication circuitpen pressure information, side switch information and identification information ID are to be transmitted, and so forth and performs an initial setting process in accordance with the determinations to perform an initial setting.

It is to be noted that, in the foregoing description, the signal Sp for pairing is transmitted from the position indicator, and when the signal Sp is received by the position detection system, the position detection systemsends information indicating a configuration type to the position indicatorand then the position indicatorperforms the initial setting process on the basis of the information indicating the configuration type. However, the position detection systemmay transmit a signal Sp for pairing intermittently in a fixed period To to the position indicatorvia the wireless communication circuit. In this case, the signal Sp for pairing includes information indicating a configuration type of the position indicator which is to act together with the position detection system.

In this case, when the position indicatorreceives the signal Sp from the position detection system via the wireless communication circuit, it performs the initial setting process using the information indicating the configuration type included in the signal Sp. Then, after the initial setting process is completed, the position indicatortransmits a response signifying that the signal Sp for pairing is received and pairing is completed to the position detection system.

If pairing is performed in such a manner as described above and the initial setting process in the position indicatoris completed, then the position indicatorprepares to start transmission of a stylus position signal and additional information to the position detection system in accordance with the initial setting process. Further, if the position detection systemrecognizes that pairing with the position indicatoris possible, then it stops the transmission of the signal Sp via the wireless communication circuit and instead sends a reference signal (external synchronizing signal) for a transmission timing of a signal from the position indicatorto the position indicatorvia the wireless communication circuit.

The transmission of a stylus position signal and additional information from the position indicatorto the position detection systemis performed in synchronism with a signal (external synchronizing signal) from the position detection system received by the wireless communication circuit. Consequently, in the position detection system, a signal from the position indicatorcan be received with certainty and accuracy.

Several examples of how to establish synchronism between the position indicatorand the position detection systemafter pairing between the position indicatorand the position detection systemis established are described with reference to rows B, C, and D of. It is to be noted that the examples of rows B and C ofare directed to a case in which the position indicatortransmits all of a stylus position signal and additional information to the position detection systemvia the center electrode(or the peripheral electrode), and the example of row D ofis directed to another case in which a stylus position signal and pen pressure information within additional information are sent to the position detection systemvia the center electrode(or the peripheral electrode) while identification information ID is sent to the position detection systemvia the wireless communication circuit.